The present invention relates to a water jacket structure for an outboard motor. More particularly, the invention concerns a water jacket structure having an installation portion for installing an electrical component of an outboard motor.
Generally, an outboard motor has an intake system, an exhaust system, and electrical components around an engine of the outboard motor, and these systems, and components are enclosed by an engine cover. The electrical components are exothermic bodies. Also, the electrical components are often exposed to heat from the engine. Because the electrical components are exposed to extremely high temperatures, ample cooling is necessary to ensure the operation of the electrical components.
A common method of cooling the electrical components is to provide radiator fins in a housing case of the electrical components, and to expose this case to cool air from, for example, a flywheel. Cooling electrical components by the cool air from the flywheel, however, does not necessarily provide an adequate cooling effect. Without adequate cooling, the efficiency of the electrical components decreases, or in some instances, the electrical components may break down. The radiator fins may be enlarged to increase its cooling efficiency. However, the enlarged radiator fins increase the housing size of the electrical components, and take up more space in the outboard engine.
Furthermore, radiated heat from the electrical components and the size of the electrical component increase as the capacity of the electrical components increases. Because an adequate distance must be obtained between the electrical components and other parts of the outboard motor, it becomes difficult to design the component layout of the outboard engine.